In the mobile telecommunications network, the demands for value-added services based on user location information, such as map navigation and localized advertisement, are ever increasing. A value-added service provider can provide more localized and more personalized service content to a user according to the location information provided by the network. It can be known from the above description that, in order to implement the value-added services, the mobile telecommunications network is required to have the capability of locating a user terminal.
The Worldwide Interoperability for Microwave Access (WiMAX) defines the architecture of a Location-based Service (LBS). When a location-based service is implemented in the architecture, a client usually specifies the required Quality of Service (QoS) when the client sends a location request to a location server (LS), and the QoS may include the location precision and location delay. The location delay is a time interval between sending a location request and receiving a location result, and is used for guaranteeing the time effectiveness of the location result. The location precision includes horizontal precision and vertical precision, and is used for guaranteeing the accuracy of the location result.
During research on the prior art, the inventor finds that in the implementation of a location-based service, usually a client sends a location data request to an LS. The location data request includes specific QoS requirement values such as the horizontal precision, the vertical precision and the location delay. The LS obtains the location result by interacting with a location controller (LC). If the location result does not satisfy the QoS requirement values, the LS will not send the location result to the client, but return a location failure indication only. However, for a service that does not have specific QoS requirements for the location result, if a map location service with the highest possible precision is provided to a user terminal, the above method will make the network unable to determine the QoS of the location result according to its own location capability. Furthermore, because the network location capability is also affected by many factors, such as the distribution density of base stations (BSs) or the blockage of buildings, the location can be successful only when the QoS requirement is lower than the location capability of the network. It can be seen that, the location-based service cannot fully utilize the location capability of the network, and the location process for implementing a location service QoS request lacks flexibility.